Which cycles rendering pass is antialiased
You need to know, that there is nonstandard algorithm to get anti-aliasing in cycles instead normal render. Each pass in cycles also is an anti-aliasing pass too. Each pass specifies the color, shadow and antialiasing at same time:



And cycles has a setting to manipulate how far each pixel sample can deviate to get anti-aliasing: 



Making the filter size value smaller will squeeze the samples more into the center. So there is no option to turn off anti-aliasing, but you can make filter size at minimum to get similar result: